Google it if you need to. Here’s the product description from SupplyHouse dot com. This is a beast of a water heater in excellent condition.
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60 Gallon BTH-120 120,000 BTU Cyclone Mxi Commercial Gas Water Heater (NG)
ENERGY STAR certified - Up to 95% thermal efficiency dramatically lowers operating costs
Intelligent Demand Response control system senses large water draws and automatically adjusts the differential setpoint, increasing the hot water available when it is needed the most
Submerged combustion chamber, with helical heat exchanger, positioned in center of tank, surrounded by water to virtually eliminate radiant heat loss from chamber
iCOMM remote monitoring provides detailed diagnostic fault notifications and control of the set point and differential using the free A.O. Smith app
Mechanical venting versatility with convention power venting or direct venting vertically or through side wall with low cost PVC Schedule 40 intake and exhaust pipe
Direct-vent intake and exhaust pipe can terminate separately outside building or through single opening, using concentric vent assembly
High efficiency modulating down-fired pre-mix burner provides optimum efficiency and quiet operation
Permaglas Ultra Coat glass lining coating is applied using a liquid slush coating technique to ensure uniform coating